If 3 raise to power 2y -6(3raise to power y) =27

Answer 1

3^(2y) - 6(3^y) = 27

let 3^y = u
then we have:
u^2 - 6u - 27 = 0
(u - 9)(u + 3) = 0
u = 9 or u = -3

if u = 9, the 3^y = 3^2 -----> y = 2
if u = -3, then 3^y = -3 , which is not possible, so

y = 2